This invention relates to improved methods of stimulating the flow of fluids through subterranean formations using organic liquid based liquids, the viscosity of which is increased using novel organic phosphoric acid esters and salts thereof. Representative art relating to these types of compounds, their preparation and use are found in U.S. Pat. Nos. 2,245,649; 2,274,302; 2,329,707; 2,346,155; 2,885,417; 2,905,683; 2,983,678; 2,983,679; 3,010,903; 3,331,896; 3,470,222; 3,494,949; 3,505,374; 3,547,820; 3,575,859; 3,584,087; 3,706,822 and 3,757,864, the teachings of which are specifically incorporated herein by reference.
Other patents made of record in the parent application include U.S. Pat. Nos. 1,944,530; 2,005,619; 3,020,303; 3,133,787; 3,484,474; 3,755,509; 3,757,864; and British Pat. No. 1,415,190, which is equivalent to Canadian Pat. No. 974,539.
Organic phosphoric acid esters have been employed in their free acid form and/or salts thereof as detergents, lubricating liquids, corrosion inhibitors, friction reducing agents, thickening agents and the like.
U.S. Pat. No. 3,757,864 teaches that certain aluminum salts of organic phosphoric acid esters are useful as friction reducing and gelling agents for nonpolar organic liquids. The salts are formed by reacting a basic aluminum compound with an ester which has been formed by reacting one or more monohydric aliphatic alcohols with a phosphorus compound such as P.sub.2 O.sub.5, phosphorus oxychloride, PCl.sub.5, PF.sub.5, and the like.
It has now been discovered that certain metal salts of complex reaction products of a hydroxy ether and a phosphorus compound such as P.sub.2 O.sub.5, are at least as effective as, and in many instances more effective than, the agents disclosed in U.S. Pat. No. 3,757,864 to gel refined oils and certain crude oils.